Ptychography

Ptychography is a special kind of scanning transmission X-ray microscopy (STXM). A sample is illuminated through a small hole with a narrow, coherent X-ray beam at a synchrotron. The sample is scanned through the beam with a step size about five to ten times smaller than the beam diameter. At each step a far field image of the diffraction pattern is captured with a large area CCD-camera. From the entity of these pictures an image of the sample can be reconstructed via iterative Fourier re-transform calculations.